Coinsurance: Instead of, or in addition to, paying a fixed amount up front (a co-payment), the co-insurance is a percentage of the total cost that insured person may also pay. For example, the member might have to pay 20% of the cost of a surgery over and above a co-payment, while the insurance company pays the other 80%. If there is an upper limit on coinsurance, the policy-holder could end up owing very little, or a great deal, depending on the actual costs of the services they obtain.
The Commonwealth Fund, in its annual survey, "Mirror, Mirror on the Wall", compares the performance of the health care systems in Australia, New Zealand, the United Kingdom, Germany, Canada and the U.S. Its 2007 study found that, although the U.S. system is the most expensive, it consistently under-performs compared to the other countries.[6] One difference between the U.S. and the other countries in the study is that the U.S. is the only country without universal health insurance coverage.
Persistent lack of insurance among many working Americans continued to create pressure for a comprehensive national health insurance system. In the early 1970s, there was fierce debate between two alternative models for universal coverage. Senator Ted Kennedy proposed a universal single-payer system, while President Nixon countered with his own proposal based on mandates and incentives for employers to provide coverage while expanding publicly run coverage for low-wage workers and the unemployed. Compromise was never reached, and Nixon's resignation and a series of economic problems later in the decade diverted Congress's attention away from health reform.
The term managed care is used to describe a variety of techniques intended to reduce the cost of health benefits and improve the quality of care. It is also used to describe organizations that use these techniques ("managed care organization").[96] Many of these techniques were pioneered by HMOs, but they are now used in a wide variety of private health insurance programs. Through the 1990s, managed care grew from about 25% US employees with employer-sponsored coverage to the vast majority.[97]
In 2003, according to the Heartland Institute's Merrill Matthews, association group health insurance plans offered affordable health insurance to "some 6 million Americans." Matthews responded to the criticism that said that some associations work too closely with their insurance providers. He said, "You would expect the head of AARP to have a good working relationship with the CEO of Prudential, which sells policies to AARP's seniors."[83]

Americans are required to carry medical insurance that meets federally designated minimum standards or face a tax penalty. In certain cases, taxpayers may qualify for an exemption from the penalty if they were unable to obtain insurance due to financial hardship or other situations. Two public health insurance plans, Medicare and the Children's Health Insurance Program, target older individuals and children, respectively. Medicare also serves people with certain disabilities. The program is available to anyone age 65 or older. The CHIP plan has income limits and covers babies and children up to the age of 18.

Effective group health plan years beginning after September 23, 2010, if an employer-sponsored health plan allows employees' children to enroll in coverage, then the health plan must allow employees' adult children to enroll as well as long as the adult child is not yet age 26. Some group health insurance plans may also require that the adult child not be eligible for other group health insurance coverage, but only before 2014.[78]
The shared responsibility provision is part of the Affordable Care Act, also known as ACA or Obamacare. The goal is to ensure that all US citizens and permanent residents have access to quality health insurance. Any non-resident aliens, including international students on F, J, M and Q visas (and certain family members of students) are not subject to the individual mandate for their first 5 years in the U.S. All other J categories (teacher, trainee, work and travel, au pair, high school, etc.) are not subject to the individual mandate for 2 years (out of the past six).
In November 2017, President Trump directed "the Department of Labor to investigate ways that would "allow more small businesses to avoid many of the [Affordable Care Act's] costly requirements."[81] Under the ACA, small-employer and individual markets had "gained important consumer protections under the ACA and state health laws — including minimum benefit levels."[81] In a December 28, 2017 interview with the New York Times, Trump explained that, "We've created associations, millions of people are joining associations. ...That were formerly in Obamacare or didn't have insurance. Or didn't have health care. ...It could be as high as 50 percent of the people. So now you have associations, and people don't even talk about the associations. That could be half the people are going to be joining up...So now you have associations and the individual mandate. I believe that because of the individual mandate and the association".[85]
Public insurance cover increased from 2000–2010 in part because of an aging population and an economic downturn in the latter part of the decade. Funding for Medicaid and CHIP expanded significantly under the 2010 health reform bill.[9] The proportion of individuals covered by Medicaid increased from 10.5% in 2000 to 14.5% in 2010 and 20% in 2015. The proportion covered by Medicare increased from 13.5% in 2000 to 15.9% in 2010, then decreased to 14% in 2015.[3][10]